x86: replace CONFIG_X86_SMP with CONFIG_SMP

The x86/Voyager subarch used to have this distinction between
 'x86 SMP support' and 'Voyager SMP support':

 config X86_SMP
	bool
	depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)

This is a pointless distinction - Voyager can (and already does) use
smp_ops to implement various SMP quirks it has - and it can be extended
more to cover all the specialities of Voyager.

So remove this complication in the Kconfig space.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/vmiclock_32.c b/arch/x86/kernel/vmiclock_32.c
index c4c1f9e..a4791ef 100644
--- a/arch/x86/kernel/vmiclock_32.c
+++ b/arch/x86/kernel/vmiclock_32.c
@@ -256,7 +256,7 @@
 	 */
 	clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
 	local_irq_disable();
-#ifdef CONFIG_X86_SMP
+#ifdef CONFIG_SMP
 	/*
 	 * XXX handle_percpu_irq only defined for SMP; we need to switch over
 	 * to using it, since this is a local interrupt, which each CPU must